package juc;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/*
 * 多线程之间按顺序调用，实现A->B->C, 三个线程启动，要求如下：
 * AA打印5次，BB打印10次，CC打印15次,接着,AA打印5次，BB打印10次，CC打印15次,来10轮  
 */
public class ThreadOrderAccess {
    public static void main(String[] args) {
        ShareResource sr = new ShareResource();
        
        new Thread(() -> {
            for (int i = 1; i <= 10; i++) {
                sr.print5(i);
            }
        }, "AA").start();
        new Thread(() -> {
            for (int i = 1; i <= 10; i++) {
                sr.print10(i);
            }
        }, "BB").start();
        new Thread(() -> {
            for (int i = 1; i <= 10; i++) {
                sr.print15(i);
            }
        }, "CC").start();
    }
}

class ShareResource {
    private int number = 1;
    // 一锁多钥匙
    private Lock lock = new ReentrantLock();
    private Condition c1 = lock.newCondition();
    private Condition c2 = lock.newCondition();
    private Condition c3 = lock.newCondition();

    public void print5(int totalLoopNumber) {
        lock.lock();
        try {
            // 1 判断
            while (number != 1) {
                // A 就要停止
                c1.await();
            }
            // 2 干活
            for (int i = 1; i <= 1; i++) {
                System.out.println(Thread.currentThread().getName() + "\t" + i);
            }
            // 3 通知
            number = 2;
            c2.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void print10(int totalLoopNumber) {
        lock.lock();
        try {
            // 1 判断
            while (number != 2) {
                // A 就要停止
                c2.await();
            }
            // 2 干活
            for (int i = 1; i <= 2; i++) {
                System.out.println(Thread.currentThread().getName() + "\t" + i);
            }
            // 3 通知
            number = 3;
            c3.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void print15(int totalLoopNumber) {
        lock.lock();
        try {
            // 1 判断
            while (number != 3) {
                // A 就要停止
                c3.await();
            }
            // 2 干活
            for (int i = 1; i <= 3; i++) {
                System.out.println(Thread.currentThread().getName() + "\t" + i);
            }
            // 3 通知
            number = 1;
            c1.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }
}